Come Join Horticulturists Rose Hiskes and Dr. Charlotte Pyle at the Scotland Library!  Take A Walk and Learn More About Invasive Plants.  The program is free of charge, and lunch will be provided. 

On August 30th, 2025 from 10 AM to 1 PM rain or shine you are welcome to join The Scotland Invasive Plant Working Group, and our guests Rose Hiskes and Dr. Charlotte Pyle at the Scotland Library to learn about invasive plants. This program is limited to 12 participants.  Registration needs to be made by August 8th.  If you would like to attend, contact Rose.Hiskes@ct.gov to register.

Take a walk with us along the boardwalk trail through the woods at the Scotland Library.  We will be accompanied by horticulturists Rose Hiskes of the Connecticut Invasive Plant Working group and the Connecticut Agricultural Experiment Station and Dr. Charlotte Pyle a forest and landscape ecologist, and co-chair of the Connecticut Invasive Plant Working Group.  

The first part of the event will be an interesting learning opportunity with Rose pointing out both native and invasive plants along the way.  She will explain various methods of identification methods observing foliage, bark, flowers, and various other growing characteristics. She will make recommendations on how the invasives can best be eliminated or at least controlled.  Dr. Pyle will suggest alternative native plantings that we could add that would be adaptable to the environment along the trail once the invasives are removed.  

Our town is providing lunch at no cost to attendees.  After lunch, we hope to begin removal of some of the invasive plants.  If you have never walked here, I would describe it as a beautiful little trail, actually an elevated boardwalk, that begins in front of the Scotland Public Library and connects via town land to the fire station.  The trail is definitely worthy of some cleanup and landscaping. Attendees should wear appropriate footwear, as we will be working in the wooded areas alongside the boardwalk.  Prepare for ticks by tucking pants into socks.  Bring a pruner and gloves.  This is a rain or shine event, so hopefully the weather will cooperate!   

 

                                                            Callery Pear in Bloom

                                     Sharp thorn-like growths

                                           The Round Fruit

Callery Pear AKA Pyrus calleryana

This spring, for the first time, I noticed a small attractive tree with showy white flowers growing near the border of a state-owned field across from our house.  It being something new to me, I snapped a picture of it and asked my smart phone for an ID.  The phone readily complied suggesting the tree was a wild Callery pear tree.  In searching for more information, I found first of all that The Id. provided by my phone was correct, and secondly that these trees are yet another invasive plant. 

Here is a tad of history about how they arrived on our shores and how they became invasive should you be interested.  The trees were brought here from China, along with many other plants, during the early 1900's.  It is during this time period that ranching in the Pacific Northwest began to transition to farming. Many trees and plants likely to survive in that climate were transported from not only various parts of the United States, but from other countries as well.  Great emphasis was placed on exploring China for potential imports as the climate in parts of China was similar to that of the Pacific Northwest. It was believed plants from those areas in China would likely survive and thrive here.  Previously, in the Pacific Northwest, orchards had been planted with numerous French pear trees. Sadly, multitudes of these trees were succumbing to a disease called fire blight.  A diseased tree would exhibit branches and leaves that appeared shriveled, looking exactly as though they had been through a fire.  Just in the nick of time plant explorers in China discovered the extremely hardy Callery pear tree.  The trees were so self-preserving they even had spiny thornlike growths along their branches which deterred wildlife from grazing on them.  Grafting the French pear trees to Callery pear rootstalk seemed like the perfect solution for the survival of the diseased French pear trees.  Callery pear seeds were imported from China by the thousands and from them thousands of trees were successfully grown, and varieties of the less hardy pear trees were then grafted to them.  Problem solved?  Well yes and no. The fire blight issue was resolved, but let's fast forward to the year 1952.  This is when John Creech from the USDA happened to observe one of the older remaining Callery pear trees that was being grown as potential rootstalk.  The glossy leaves, the globular form, and tree's showy bloom struck him as very appealing.  Additionally, this particular Callery pear tree did not exhibit the usual sharp thorn like spurs on its branches.  Seeing its potential as a landscape tree, he started several scions, essentially clones, from cuttings of the tree's branches and named the resultant trees Bradford pear trees. The USDA continued to grow more and more of these clones. During the housing boom in the 1960's, the Bradford pear trees were heavily marketed.  After the successful marketing campaign, the trees were found just about everywhere.  Bradford pear trees are not self-fertile.  Even if you plant two Bradford pear trees near each other they are essentially sterile. Therefore, Bradford pear trees could safely be grown as ornamental trees without danger of overpopulating the environment. 

By the 1980's, as the trees matured, problems with branch breakage, sometimes resulting in total tree breakage, began to occur. Since the tree was such a popular ornamental, alternative cultivars were developed, each, on its own, essentially sterile.  This is where the invasive outlaw problem began.  Unfortunately, the several different cultivars of Callery pear trees developed and marketed in the 1980's, though sterile individually, were able to cross pollinate with each other. They could also cross pollinate with the Bradford pear.  In addition, the new cultivars were capable of cross pollination with cultivated orchard varieties of fruit bearing pear trees.  The seeds and resultant trees from cross pollinated ornamental pear trees reverted to the original imported Callery pear trees with all of their wild traits, including the trait of those tough sharp 4" thorn like spines!  The wild Callery pear trees are no longer sterile.  They bear numerous small round fruit each containing several seeds within.  As some of that fruit is consumed by birds, the seeds pass through their digestive tracts and are scattered through the landscape while the birds are on their travels.  Eventually these seeds germinate creating a new colony of wild thorny pear trees also capable of reproducing.  Any fruit not consumed drops close to the original tree and germinates in place beginning the creation of a thicket of these invasive trees.  As if that is not enough, the trees send out lateral roots occasionally sending up shoots forming yet more trees. Dense thickets of these thorny trees can prevent wildlife from passing through and birds from nesting.  Woodland areas infested with these invasive trees become unpassable for human recreational activities as well.

So, how exactly did that tree get in the field across from our house?  I believe the Bosc and Bartlett pear trees growing in our orchard somehow became cross pollinated with a Callery pear tree, either a wild one or somebody's ornamental.  Several years ago, a gang of criminal squirrels harvested our entire crop of perfectly ripened pears for themselves. They are the likely culprits responsible for planting the Callery pear tree I observed in that field, and I fear there will be more!  

You can readily identify a wild Callery pear tree.  Its leaves look glossy and similar in form to that of a regular pear tree.  The wild Callery pear has the numerous sharp woody thorns that grow along its branches.  Another identifying characteristic of either wild or cultivated Callery and Bradford pear trees is the abundant showy white flowers which are said to smell like rotting fish or urine.  The odor attracts flies which are the trees primary pollinators. I have to say I did not notice that odor when I photographed the wild pear in the field for smart phone identification, but I did not get all that close to the tree either. Callery pears are considered invasive in many states including Connecticut.  According the UCONN invasive plant list, Callery pear cultivars will be banned for sale in Connecticut beginning in 2027.  Beware! as of 2025 Bradford pear and Callery pear cultivars are still being sold in Connecticut!!  There are many attractive native alternatives that bear flowers that don't smell like urine or rotting fish! Select one of those instead.

 

Second year in bloom

First year rosette

Spotted Knapweed - AKA Centaurea maculosa, Centaurea steobe

This is a plant I am a bit sorry to see on the outlaw list.  I am sure you have seen it in town and growing in patches along the highways.  The plant produces lots of pretty pink flowers in July often in areas you wouldn't believe anything could possibly grow.  It often frequents neglected areas with sandy gravelly soil, for example our town transfer station, along railroad tracks, sandy roadside ditches, vacant lots, etc.  I used to believe this plant, with its attractive summer blooms, added an aspect of hope to sites otherwise devoid of beauty. At one point I actually thought about adding it to one of my gardens.  Fortunately, I did not.  With its aggressive growth habits, I definitely would have regretted it.  One really shouldn't move plants from the wild to one's own garden until it is known exactly what you are dealing with, or for that matter if it is even legal.  

Spotted knapweed, a member of the aster family, is native to Western, Central, and Eastern Europe where it along with other plants from the Centaurea genus, has an ancient history of medicinal use.  It is considered a biannual forming a short rosette of leaves in its first year.  During its second year it grows to a height of about two feet and produces flowers.  The flowers are a good source of pollen and nectar for our native bees as well as honeybees which are native to 

Europe imported here during the 1600's.  Interestingly honeybees when first introduced were referred to as White Man's flies by Native Americans.  Spotted knapweed is among several plants employed by beekeepers to increase honey yield.  While that may prove profitable in the near term, if invasive species are allowed to take over, the lack of variety of nectar and pollen throughout the season by native plants is guaranteed to have a negative effect on native bees as well as honeybees.  Spotted knapweed is an extremely prolific seeder, with a single healthy plant producing around 1000 seeds.  With that quantity of seed production this plant has the capacity of crowding out native plants, additionally it is yet another invasive plant with allelopathic properties, producing a chemical that discourages other plants from growing near it.  Fortunately, seed production is this plants primary means of spread.  When colonies are growing on sandy riverbanks the likelihood of erosion increases because of this plant's frail root system which does not hold the soil in place very well, especially during heavy water flows.  With its heavy seeding, if in a pasture setting, spotted knapweed has the capacity of rapidly taking over grazing areas providing less diverse food for wildlife and certain livestock.  

 How To Remove

Small colonies can be easily managed by hand pulling with help of a shovel or trowel.  The use of gloves is recommended as some may have a sensitivity to this plant.

Herbicides containing 2,4-D, Triclopyr, or Dicamba are also recommended.  To be most effective and prevent seed spread they should be applied during the time when the plant is in it budding stages, before flowers open.  Monitoring of the area and repeat application will be required as past fallen seeds remain viable for a number of years.

Biological Control

Sheep, goats and cattle will readily consume spotted knapweed in all its growing stages but especially when it is in its bolting stage, the period in mid-July when it begins to form buds and flowers. The plant has a nutrition profile similar to alfalfa when it is in its rosette stage with nutrition declining slightly when the plant is bolting. Repeated grazing will significantly reduce the presence of this invasive plant allowing for more diverse pasturage. 

Over the years several different insects have been introduced as a biological control for spotted knapweed.  Some target the flower or seed heads dramatically reducing the number of seeds the plant sets.  Other insects or their larvae damage the roots. Still others weaken plant by feeding on its leaves. The following list was taken from the USDA:

The sulfur knapweed moth (Agapeta zoegana) larvae feed within the plant's roots. The knapweed peacock fly (Chaetorellia acrolophi) larvae feed on the plant's seeds. The green clearwing fly (Terellia virens) larvae feed on seeds within flowerheads of spotted knapweed. The knapweed root weevil (Cyphocleonus achates) larvae feed within spotted knapweed roots. Larinus minutus, a seedhead weevil, larvae destroy spotted knapweed seed in the seedheads. Larinus obtusus, blunt knapweed flower weevil, larvae feed on seeds within the seedheads and adults feed on leaves. Urophora affinis and Urophora quadrifasciata are seedhead gall flies that are also used as biocontrol agents for spotted knapweeds. It is perfectly legal to move a plant that is infested with any of these insects to an area of plants not yet infested.

 

                                CYPRESS SPURGE AKA Euphorbia cyparissias

During the 1860's Cypress spurge was imported from Eurasia for its decorative appeal. Likely because of its low maintenance nature, it was frequently planted in graveyards, so much so that one of its common names is graveyard weed. Cypress spurge is a groundcover with fine narrow leaves growing in alternate pairs along the stem that eventually form whorls along the upper portion.  When in bloom, the plant is loaded with an abundance of small pretty yellow flower clusters giving it a very attractive appearance. Another of the plants characteristics is the milky substance that is exuded from the stem or root when either are broken.  This toxic lactic substance can cause contact dermatitis in some people. Originally intended as an ornamental groundcover, the plant readily escaped cultivation and has now achieved its present outlaw status. The plant is considered potentially toxic to horses and cattle, though most grazing animals will instinctively avoid it.  When I started one of my gardens, shortly after moving here, I noticed this volunteer plant growing along the back edge.  I welcomed it and encouraged it to grow.  Quickly realizing that it did not need any encouragement, my intentions changed, and I began trying to eradicate it.  It has been over 20 years now and I have yet to become successful in that endeavor.  The plant has a trailing rhizome type of root system that can reach up to ten feet.  The root readily breaks off as you pull it and new plants form from lateral buds all along the remaining root segments; so, it continues to grow in the back of my garden along the tree line right next to the poison ivy adding another level to my exasperation. As you can imagine the plants abundant flowers eventually produce abundant seeds, up to three seeds to a capsule, and to make matters even worse, the mature seed pods explode propelling the seeds up to 16 feet away!  Take my advice DO NOT ENCOURAGE THIS INVASIVE VINE!  As is true of all invasive non-native plants, the aggressive growth of Cypress spurge crowds out native species.  Because of the lactic substance exuded it is not considered a grazing plant, in fact this plant not considered beneficial for any of our native wildlife.

HOW TO REMOVE

If this plant is growing in your garden, you can attempt its eradication by pulling it. You can contain the spread this way but if you don't pull out the entire root the plant will continue to exist in your garden.  Though I have not had an issue with contact dermatitis, I suggest wearing gloves to prevent possible a possible occurrence from contact with the sap.  The most effective control method is to apply an herbicide such as glyphosate.  You will likely need to repeat application during the growing season.  If Cypress spurge is growing in your lawn or in a horse or cow pasture, the recommendation is repeated mowing every 21 days after the first bloom.  It is important to continue the 21 day mowing process as mowing encourages new growth.  If the plant is already in seed mow around it so as not to encourage further spread of the seed.  Eventually consistent mowing during the plant's growing season should deplete the plant of its growth energy.  Another herbicide you might consider is 2,4-D amine.  The first application should be at early bud stage.  A second application will be needed during the plant's growing season.  This can be a difficult plant to eradicate in a livestock pasture setting.

Biologic control

There are at least two insects that will help to limit growth of the plant.  The brown dot leafy spurge beetle Aphthona cyparissiae, and the black leafy spurge flea beetle Aphthona lacertosa.  These insects lay their eggs at the root base of the plants.  The larvae feed on the roots and the adult beetles feed on the foliage.  Actually, there have been 11 species of European insects released in North America to help control this plant.  It seems none have found the Cypress spurge in the back of my garden, at least not yet!

 

              Common Reed - Phragmites australis australis

This plant was unintentionally introduced from Europe in the late 1700's or early 1800's.  The seed likely hitched a ride either among ship's ballast, or from reeds used as protective packing material when fragile items were shipped. As with many invasives, the plant is not all bad. Most parts of the plant are edible with young shoots said to be similar in taste and texture to bamboo shoots.  If common reed is growing in a marsh, livestock will graze on it.  The plant can even be used as a construction material.  In parts of Europe this is one of the plants used for thatching roofs.  Additionally, the extensive root system is able to help filter out impurities from polluted water.  So, what is so bad about this plant?  Our native species of Phragmites called Phragmites australis americanus is diminutive in comparison. The native Phragmites, along with other native wetlands or bog plants, all of which are called helophytes, are rapidly being crowded out by the invasive behemoth Phragmites australis australis.  The invasive version, which has essentially conquered the world, has an incredibly aggressive growth pattern. It reaches an approximate height of 19 feet shading and crowding out our 6 1/2-foot native Phragmites, as well as any other native helophytes desiring an opportunity to grow.  Invasive common reed grows from seed as well as from rapidly spreading rhizomes (horizontal underground roots) and stolons (above ground horizontal shoots).  The rhizomes can grow 6 feet per year, so you can see how quickly Common Reed can spread forming a monoculture. You often see Invasive Common Reed growing in wetland habitats around ponds, drainage ditches, rivers, streams, and even in brackish water estuaries along Connecticut's beaches.  This plant is not terribly particular about where it will take root.  It will grow just about anywhere if the ground is soggy.  In Scotland, if you travel along Rt. 97 from the center of town toward Baltic you will notice an attractive little marsh and pond on the left just a little past The Highland Campground.  Phragmites australis australis has established a sizable colony there.  It looks quite lovely with its frothy plumes blowing in the summer breeze however left to its own devices for too long it may eventually guzzle down the entire the pond!  Seriously, it really does have the capacity of lowering a water table, and it can also alter water flow in areas along brooks or streams, but the main problem, as with all the other invasive plants we have been discussing, is that Common Reed is displacing native plants as well as the animals that require native plants for their survival. This plant's aggressive growth habits easily keep native species, both plants and animals, from growing and thriving in its midst. 

How To Remove

I guess another of the reasons this plant has inherently conquered the world is, once it gains a foothold, its removal is a task involving some significant labor.  A way to remove Phragmites australis australis without using herbicides is a marvelously murderous sounding method that could be the title of a pulp murder mystery called "Cut to Drown".  This method involves hand cutting the plant to a level six inches below the water level. As a less physically taxing alternative to hand cutting, one might try a gas-powered aquatic vegetation cutter.  A simple internet search will bring up several to peruse.  These cutters are specifically designed for the task of cutting vegetation under the water level in lakes and ponds. Cutting below the water level starves the plant of the oxygen it requires to survive.  Cutting should be done from mid spring to mid fall.  The plant should not be cut when it is in its dormant stage from mid fall to early spring.  When cutting, every piece of greenery needs to be cut below the water surface because, believe it or not, the plant can "snorkel" and will survive if any piece of leaf or stem remains above water.  The cut canes should be placed in a tarp, as you are cutting them, for removal.  All cut canes need to be removed from the area.  Proper disposal method is bag and burn. The area will need to be monitored, and this process may need to be repeated periodically as new growth forms.

A slightly different option requires a controlled burn.  With all required permits and a trained team in place, a prescribed burn can be done ahead of the cut to drown procedure.  This will eliminate the bulk of the reeds requiring removal and disposal. The burn should be done when the plant is in its dormant and dry stage during late fall to early spring.  When considering a controlled burn, great care needs to be taken to avoid loss of wildlife and native plants.  A burn will only remove the portion of the plant that is above water.  It will not kill the rhizomes, stolons, or any portion of the plant below the water line.  It will make the task of cut to drown procedure a little easier once the plant is back in its growing cycle as there will be significantly less biomass to remove.

Yet another method- Please don't shoot the messenger! I know nobody wants to hear this, but the most common method used to eliminate this plant, and many other invasive helophytes, involves the use of herbicides.  While none of us like the thought of using herbicides in our ponds lakes or waterways, keep in mind any aquatic environment filled with invasive weeds is not good for native wildlife or plant life either, so here goes- There is a Glyphosate solution specifically created for aquatic use, and there are other herbicide solutions specifically designed for pond and lake use that contain various other active ingredients besides Glyphosate as well, with each targeting a different plant.   Of course, all herbicides need to be applied using great precision and care so as not to damage any native plants or aquatic wildlife.  A chart which detailing herbicide application for this plant can be viewed at the Michigan's Citizens Guide by copying and pasting or clicking on the following link.  

https://www.greatlakesphragmites.net/files/HerbicideQuickGuide.pdf .  

The entire website, which you should be able to access from the above link, has lots of information on the control of this plant.  I promise this site is not all about using herbicides!  Michigan has approximately 11,000 lakes of all sizes so they might be considered experts on the topic of eradicating invasive plants from waterways!

The link below to the Connecticut Agricultural Experiment Station provides clear photos showing the various differences between native and non-native Phragmites.  You may need to copy and paste the below link to get it to open.

https://portal.ct.gov/-/media/caes/documents/publications/fact_sheets/plant_pathology_and_ecology/phragmitesfactsheetpdf.pdf

 

Burning Bush AKA Winged Euonymus, Euonymus alatus

This plant is native to central and northern China, Japan and Korea where it is used in traditional Chinese and Korean medicine.  Burning bush was introduced to the United States as an ornamental in the 1860's. It was considered desirable for its colorful berries and bright red or pinkish red foliage displayed during the autumn season. Winged euonymus gets the "winged" portion of one of its common names from the unusual appearance of its branches which have distinctive thin corky ridges along opposing edges that resemble wings.  Because of this shrub's hardiness and its attractive fall foliage, it was frequently selected as a decorative hedge planting along interstate highways. The plant is not especially fussy about where it lives.  It will grow in sun or shade, and it is adaptable to most soil types.  Wherever it grows it produces abundant seeds that birds and small mammals relish.  Though that seems a good thing, unfortunately as the seeds pass through the digestive tract of these birds and mammals they remain fertile and are deposited far from the original feeding site.  In this new site seeds germinate and form new colonies.  Like several other shrubs considered invasive, burning bush can also take root from any branches that contact the ground.  This is called vegetative propagation.  Over the years this plant, like many other invasives, has escaped cultivation and has naturalized in our woodlands where it chokes out native plants.  Given its aggressive growth habits this shrub will continue to spread. Some studies suggest that it will even out compete other invasive plants!  In much of New England, including Connecticut, it is not legal to purchase, propagate, or transport this shrub or any of its cultivars. Having an awareness of the impact this shrub can have on our woodlands and open fields; you might want to seriously consider its removal should it be an ornamental shrub presently growing on your property.  There are many alternative plantings that make attractive replacements.  Inserting a native planting in place of this shrub will also help to discourage regrowth of Burning Bush from any remaining seeds that germinate after the plant's removal.  There are many to consider such as maple leaf viburnum, American holly, or winterberry.

HOW TO REMOVE

The shrub's "winged" branches make it easily identifiable no matter the season.  If you happen to spot young specimens of this plant growing in the forest, you may want to take a few minutes to remove them.  Small plants around 2 feet high or less can be quite easily pulled.  You can leave them hanging in nearby shrubs where they will dry out.  Larger specimens will require a shovel or fork to disengage the root from the soil.  It is easier to gain access to the lower part of the shrub if you first lop off most of the branches.  If you are unable to remove this shrub from the soil, another recommended option is to cut off all branches and the main trunk during its growing season and follow up with an application to the cut areas with a concentrated herbicide such as Glyphosate or Triclopyr.  To eradicate a very large infestation of this shrub, the recommendation is foliar spray of Glyphosate or Triclopyr applied during the summer growing season.  Keep in mind Glyphosate is a non-specific herbicide killing both broad leaf plants and grasses.  Triclopyr kills only broad leaf plants and will not harm grasses.

Mile-A-Minute AKA Polygonum perfoliatum or Persicaria perfoliate

Over the last several years I have seen Mile-a-Minute vine growing in several areas around Scotland and its adjacent towns.  The plant is native to India and East Asia where It is used medicinally.  Mile-a- Minute is an annual vine, one that dies back at the end of every growing season.  New plants emerge the following year, germinating from seeds that were produced by the plant the year prior. You might wonder how an annual plant that dies back completely every year can be invasive.  As its common name Mile-a-Minute suggests, the vine with its unusual triangular leaves and clusters of pretty blue seed filled berries, grows very rapidly up to 6 inches a day and up to a total of 20 to 30 feet in its one growing season! The pendulous clusters of berries drop off very easily when the vine is disturbed.  Mile-a-minute vine has tiny barb like thorns aong h stem which help it to climb adjacent trees and vegetation.  The seed containing berries fall from the vines which have climbed high up into the trees and shrubs.  They end up being widely distributed below eventually germinating and creating more plants the following year.  Some of the seeds are also consumed by birds and animals.  After passing through their digestive tracts the still viable seeds are dropped by them on their travels, thus allowing the plant to germinate and colonize in an entirely new area.  Mile-a-minute prefers to grow on wet soil in sunny locations.  It can grow along stream banks or wetlands where seed can be carried by water. 

I saw this plant for the first time many years ago when following a trail of mysterious flag like markers leading through the forest to the banks of the Shetucket River.  There it was an unusual and very distinctive looking plant that I had never seen before.  After a little sleuthing, I discovered UCONN Agriculture was doing an experiment introducing a host specific insect (a little more on that later).  More recently I noticed Mile-A-Minute growing along the roadside on Jerusalem Road in Windham, and even more recently along a roadside adjacent to a wetland here in Scotland.  Since then, I have seen it distributed in several other areas throughout our town.  Even during the winter, this is an easy plant to spot, as the remains of the vine leave a brown net like blanket over every tree and shrub covered during its summer growth.  I tried pulling some of the vine out the summer I first noticed it growing on Station Rd.  By the time I saw it, it was a little too late in the season as the vine had already developed sharp barbs and plentiful berries. The berries just tumbled off in profusion as I uprooted and pulled the vine from its supports.  Never-the-less I filled several large garbage bags before I found the vine had woven itself through a thorny multiflora rose.  It was at that point I was forced to surrender.  There is no question, an attempt to remove invasive plans can at times feel overwhelming. 

HOW TO REMOVE

For small populations of this annual plant hand pulling during its early growth is recommended.  The barbs become stiffer as the plant matures so it is easier and less physically painful to pull young plants.  Gloves will help, and it should go without saying that it is best, if possible, to pull plants before berry/seed formation.  Even immature seeds have the potential to germinate.  If infestations are larger, mowing is considered a good option.  It is best done regularly so that the plant does not get a chance to develop seeds.  If you will be  mowing, be certain to check the mower and blades afterward.  You do not want to inadvertently move seeds or plant parts to another location and start a new infestation. Another option is using a string trimmer to cut the plants to ground level.  In larger infestations preemergence herbicides can be effective.  There are a couple that are recommended, and timing of application is crucial for them to be effective.  Application instructions are a little lengthy, so I will direct you here for more information http://extension.psu.edu/mile-a-minute.com. 

Biologic Control

Back to those mysterious flag-like markers. I found that UCONN had been conducting an experiment along the banks of the Shetucket River with a host specific weevil called Rhinoncomimus latipes.  It was found that the weevil will not eliminate Mile-A-Minute, but it does weaken the plant by consuming its leaves therefore helping to stunt the plant's growth.  Interestingly the colonies of this plant that I located recently all exhibited holes in their leaves, signs that the weevil was in fact munching on the plant.  On its own, the weevil had traveled from the Shetucket River and infested all of the other colonies of Mile-a-minute plant that I discovered, so this insect is having an impact.  If you spot large colonies of this plant that are not yet hosting the weevil, it is perfectly fine to transport portions of a plant that are infested to the new area. The best long-term solution is to suppress the growth of this vine long enough for other native plants and especially trees to gain footing.  Once that happens, it should help to eliminate the sunny area mile-a-minute requires to thrive.